06901212 is referenced by 32 patents and cites 28 patents.

A digitally adaptive controller circuit for commutating a brushless, sensorless, DC motor in either of two directions adapted to receive digital back electromotive force (BEMF) detector signals. The digital circuit is driven by an input clock that is adjustable to configure the motor controller for use with a broad range of DC motors. The circuit includes commutational logic that decodes a current commutational state and a user-definable binary direction input into logic levels for digital control signals for controlling motor drive switches. The circuit also includes a signature analyzer to compare logic levels in the BEMF detector signals with expected logic levels based on an expected rotor position and direction of rotation. The digital circuit commutates the motor if the logic levels in the BEMF detector signals are at the expected logic levels. The digital circuit is compact and simple enough to be deployed onto a single programmable logic device.

Title
Digital adaptive sensorless commutational drive controller for a brushless DC motor
Application Number
10/170960
Publication Number
6901212 (B2)
Application Date
June 13, 2002
Publication Date
May 31, 2005
Inventor
James E Masino
Houston
TX, US
Agent
Conley Rose PC
Assignee
Halliburton Energy Services
TX, US
IPC
H02P 005/28
View Original Source